Load what we can from broken/truncated MIDI files.

[ardour.git] / libs / evoral / src / libsmf / smf_load.c

diff --git a/libs/evoral/src/libsmf/smf_load.c b/libs/evoral/src/libsmf/smf_load.c
index fed4d28bb7effa542f7369e8203a54a5be610047..1db09a7a458ecda1ca0a3b88084d4f79d0fa1ba9 100644 (file)
--- a/libs/evoral/src/libsmf/smf_load.c
+++ b/libs/evoral/src/libsmf/smf_load.c
@@ -83,7 +83,6 @@ next_chunk(smf_t *smf)
 
        if (smf->next_chunk_offset > smf->file_buffer_length) {
                g_critical("SMF error: malformed chunk; truncated file?");
-               return (NULL);
        }
 
        return (chunk);
@@ -282,7 +281,11 @@ expected_sysex_length(const unsigned char status, const unsigned char *second_by
        uint32_t sysex_length = 0;
        uint32_t len = 0;
 
+#ifndef NDEBUG
+       (void) status;
+#else
        assert(status == 0xF0);
+#endif
 
        if (buffer_length < 3) {
                g_critical("SMF error: end of buffer in expected_sysex_length().");
@@ -392,7 +395,10 @@ extract_sysex_event(const unsigned char *buf, const size_t buffer_length, smf_ev
 
        status = *buf;
 
-       assert(is_sysex_byte(status));
+       if (!(is_sysex_byte(status))) {
+               g_critical("Corrupt sysex status byte in extract_sysex_event().");
+               return (-6);
+       }
 
        c++;
 
@@ -435,7 +441,10 @@ extract_escaped_event(const unsigned char *buf, const size_t buffer_length, smf_
 
        status = *buf;
 
-       assert(is_escape_byte(status));
+       if (!(is_escape_byte(status))) {
+               g_critical("Corrupt escape status byte in extract_escaped_event().");
+               return (-6);
+       }
 
        c++;
 
@@ -545,7 +554,7 @@ extract_midi_event(const unsigned char *buf, const size_t buffer_length, smf_eve
 static smf_event_t *
 parse_next_event(smf_track_t *track)
 {
-       uint32_t time = 0;
+       uint32_t etime = 0;
        uint32_t len;
        size_t buffer_length;
        unsigned char *c, *start;
@@ -561,11 +570,17 @@ parse_next_event(smf_track_t *track)
        assert(track->next_event_offset > 0);
 
        buffer_length = track->file_buffer_length - track->next_event_offset;
-       assert(buffer_length > 0);
-
+       /* if there was no meta-EOT event, buffer_length can be zero. This is
+          an error in the SMF file, but it shouldn't be treated as fatal.
+       */
+       if (buffer_length == 0) {
+               g_warning ("SMF warning: expected EOT at end of track, but none found");
+               goto error;
+       }
        /* First, extract time offset from previous event. */
-       if (smf_extract_vlq(c, buffer_length, &time, &len))
+       if (smf_extract_vlq(c, buffer_length, &etime, &len)) {
                goto error;
+       }
 
        c += len;
        buffer_length -= len;
@@ -574,15 +589,16 @@ parse_next_event(smf_track_t *track)
                goto error;
 
        /* Now, extract the actual event. */
-       if (extract_midi_event(c, buffer_length, event, &len, track->last_status))
+       if (extract_midi_event(c, buffer_length, event, &len, track->last_status)) {
                goto error;
+       }
 
        c += len;
        buffer_length -= len;
        track->last_status = event->midi_buffer[0];
        track->next_event_offset += c - start;
 
-       smf_track_add_event_delta_pulses(track, event, time);
+       smf_track_add_event_delta_pulses(track, event, etime);
 
        return (event);
 
@@ -637,7 +653,7 @@ smf_event_is_textual(const smf_event_t *event)
        if (event->midi_buffer_length < 4)
                return (0);
 
-       if (event->midi_buffer[3] < 1 && event->midi_buffer[3] > 9)
+       if (event->midi_buffer[3] < 1 || event->midi_buffer[3] > 9)
                return (0);
 
        return (1);
@@ -776,6 +792,7 @@ static int
 parse_mtrk_chunk(smf_track_t *track)
 {
        smf_event_t *event;
+       int ret = 0;
 
        if (parse_mtrk_header(track))
                return (-1);
@@ -784,10 +801,10 @@ parse_mtrk_chunk(smf_track_t *track)
                event = parse_next_event(track);
 
                /* Couldn't parse an event? */
-               if (event == NULL)
-                       return (-1);
-
-               assert(smf_event_is_valid(event));
+               if (event == NULL || !smf_event_is_valid(event)) {
+                       ret = -1;
+                       break;
+               }
 
                if (event_is_end_of_track(event))
                        break;
@@ -797,7 +814,7 @@ parse_mtrk_chunk(smf_track_t *track)
        track->file_buffer_length = 0;
        track->next_event_offset = -1;
 
-       return (0);
+       return (ret);
 }
 
 /**
@@ -859,6 +876,7 @@ smf_t *
 smf_load_from_memory(const void *buffer, const size_t buffer_length)
 {
        int i;
+       int ret;
 
        smf_t *smf = smf_new();
 
@@ -876,16 +894,16 @@ smf_load_from_memory(const void *buffer, const size_t buffer_length)
 
                smf_add_track(smf, track);
 
-               /* Skip unparseable chunks. */
-               if (parse_mtrk_chunk(track)) {
-                       g_warning("SMF warning: Cannot load track.");
-                       smf_track_delete(track);
-                       continue;
-               }
+               ret = parse_mtrk_chunk(track);
 
                track->file_buffer = NULL;
                track->file_buffer_length = 0;
                track->next_event_offset = -1;
+
+               if (ret) {
+                       g_warning("SMF warning: Error parsing track, continuing with data loaded so far.");
+                       break;
+               }
        }
 
        if (smf->expected_number_of_tracks != smf->number_of_tracks) {